JPH0667757B2 - Outboard engine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an engine such as a diesel engine used for an outboard motor, and particularly to an engine having a turbocharger.

(Prior Art) Generally, an outboard motor engine is strongly required to be compact because it is arranged outside the hull. In recent years, engines equipped with turbochargers have begun to be widely used for outboard motors as well as engines for outboard motors.

(Problems to be Solved by the Invention) However, since the conventional turbocharger projects comparatively largely from the engine body, the use of such an engine in an outboard motor causes a problem that the bulk of the engine increases. .

(Means for Solving the Problems) In order to solve the above problems, according to the present invention, a crankshaft extends substantially vertically and a cylinder portion is positioned behind a crankcase in an attitude of an engine located behind a hull. The flywheel is attached to the upper end of the crankshaft. And in the present invention, the turbocharger is arranged above the engine body and behind the flywheel,
The turbine of the turbocharger is arranged behind the compressor, the intake inlet of the compressor is opened forward, and the exhaust passage of the turbine is located behind the intake inlet.

(Embodiment) FIG. 1 is a schematic vertical sectional view of an embodiment of the present invention, and FIG. 2 is a schematic view taken along the line II-II of FIG. In FIG. 1, F is the traveling direction of the ship, 1 is an outboard motor, and 2 is a hull. The engine 3 of the outboard motor 1 is V-shaped as shown in FIG. The crankshaft 5 (only the centerline is shown) of the engine 3 extends vertically, and the lower end is connected to the drive shaft 7 (only the centerline is shown) of the lower unit 6 shown in FIG. Although not shown, the lower end of the drive shaft 7 is connected to the screw shaft via a gear mechanism. The cylinder portion 11 of the engine 3 is located behind the crankcase 10, and the cylinder head portion 12 is the cylinder portion.
It is located behind 11. The crankshaft 5 projects upward from the crankcase 10, and a flywheel 15 is attached to the upper end of the projection.

A turbocharger 16 is provided behind the flywheel 15 and above the cylinder head portion 12. The turbine shaft 17 of the turbocharger 16 is in the front-rear direction (the traveling direction of the ship).
The compressor 18 is located in front of the turbine 19. The intake inlet 20 of the compressor 18 is provided at the front end of the turbocharger 16 and is open toward the front. Compressor 18 and intake outlet 21 are compressors
18 It protrudes downward from the main body, and the intake manifold 22
Connected to.

The exhaust outlet portion 25 of the turbine 19 extends rearward and downward from the turbine 19, and the lower end thereof is connected to the exhaust pipe 26. The exhaust pipe 26 extends in the vertical direction in the vicinity of the cylinder head portion 12, and the lower end thereof is connected to the exhaust pipe 27 in the lower unit 6. The exhaust pipe 27 extends to the inside of the vertical middle portion of the lower unit 6. The exhaust gas discharged from the exhaust gas outlet portion 25 of the turbine 19 is discharged into the water from the inside of the lower unit 6 through the exhaust pipes 26 and 27. Exhaust pipe above
26 is formed integrally with the exhaust manifold 28. As shown in FIG. 2, the exhaust manifold 28 extends vertically between the left and right cylinder rows, and its upper end is connected to the exhaust inlet pipe portion 29 of the turbine 19.

In FIG. 2, R is an engine center plane including the center line of the crankshaft 5, and extends vertically and in the front-rear direction in the middle portion of the cylinder rows on both sides. The turbocharger 16 is located near the engine center plane R. The intake manifold 22 extends to the outer side surface of the cylinder head portion 12 in a substantially symmetrical positional relationship centering on the engine center plane R.

In FIG. 1, the engine 3 main body and the intake manifold are shown.
The exhaust manifold 28 and the exhaust manifold 28 are housed in the engine compartment 31 inside the cowling 30. The turbocharger 16 is housed in a turbocharger chamber 33 inside another cowling 32. The upper wall of the cowling 30 is the turbocharger chamber.
The lower part of 33 is an opening, and a partition wall 35 for closing the opening is attached to the cowling 30. The partition wall 35 partitions the engine room 31 and the turbocharger room 33.
The lower edge of the cowling 32 is fixed to the upper end wall of the cowling 30 while holding the peripheral edge of the partition wall 35. The intake manifold 22, the exhaust pipe 26, and the exhaust manifold 28 are connected to the corresponding passages on the turbocharger 16 side through holes provided in the partition wall 35.

The front end wall portion and the rear end wall portion of the cowling 32 are provided with openings 38 and 39, respectively, each having a plurality of slit-shaped openings. Therefore, when the ship moves forward, outside air flows into the turbocharger chamber 33 through the opening 38 and flows out rearward through the opening 39, and a part of the air that has flowed into the turbocharger chamber 33 flows from the intake inlet 20 to the compressor 18. It is taken in.

(Effect of the invention) As described above, according to the present invention, the flywheel 15 is arranged at the upper end of the front part of the engine 3 main body.
Since the turbocharger 16 is arranged by utilizing the space formed at the rear of the 15, the total length (length in the front-rear direction) of the engine can be reduced to the same level as an engine not equipped with the turbocharger. Further, the amount of upward projection of the turbocharger 16 can be made relatively short, and the overall height of the engine can be lowered.

Furthermore, since air can be taken into the compressor 18 from the upstream side of the exhaust turbine 19 during traveling, it is possible to prevent the intake temperature from rising and improve the engine output.

In addition, from turbocharger 16 to engine and lower unit 6
Since exhaust-related passages extending to the inside of the engine can be compactly gathered in the rear part of the engine 3, damage to auxiliary machinery due to exhaust heat can be effectively prevented.

Further, the cowlings 30, 32 are configured as in the illustrated embodiment,
When the turbocharger 16 which is the maximum heat source is installed in the turbocharger chamber 33 different from the engine room 31, it is possible to effectively prevent the belts and hoses related to the engine from being damaged by the heat of the turbocharger 16.

In the structure of FIG. 2, the intake manifold 22 extends to the outside of the cylinder row, and the intake port is located outside the cylinder row. Therefore, when such an engine 3 is used as an engine not equipped with a turbocharger as shown in FIG. 3, from the intake port to the intake inertia pipe 40 from the front end of the engine 3 along both side surfaces of the engine block, It can be extended in a curved state with a large radius of curvature. Therefore, the intake resistance can be reduced and the engine output can be improved. Further, the entire engine 3 can be compactly assembled to reduce the size of the engine cowling.

[Brief description of drawings]

1 is a schematic vertical sectional view of an embodiment of the present invention, FIG. 2 is a schematic view taken along the line II-II in FIG. 1, and FIG. 3 is a schematic plan view when the engine of FIG. 2 is diverted to an engine without a turbocharger. Is. 1 ... Outboard motor, 2 ... Hull, 3 ... Engine, 5 ... Crankshaft, 10 ... Crankcase, 11 ...
Cylinder part, 15 …… flywheel, 16 …… turbocharger, 18 …… compressor, 19 …… turbine, 20 ……
Intake inlet

Claims (2)

[Claims] 1. The attitude of the engine located behind the hull
Set the crankshaft so that it extends almost vertically and the cylinder part behind the crankcase, attach the flywheel to the upper end of the crankshaft, and place the turbocharger above the engine body and behind the flywheel. , An engine for an outboard motor, in which a turbine of a turbocharger is arranged behind a compressor, an intake inlet of the compressor is opened forward, and an exhaust passage of the turbine is located behind the intake inlet. 2. The boat according to claim 1, wherein the outboard motor is provided with a turbocharger cowling that surrounds a turbocharger and an engine cowling that surrounds an engine body, and a partition wall is provided between both cowlings. Outer engine.